Revert of cc : Move screen space scale factor to root transform node

third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp

Index: third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp b/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp
index c9a0e69c05f59789890c5154bd42f6daa534e45c..c74657e3ba39534a300335674b14ab1b33f9e895 100644
--- a/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp
+++ b/third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp
@@ -453,18 +453,8 @@ class PropertyTreeManager {
 };
 
 void PropertyTreeManager::setDeviceScaleFactor(float deviceScaleFactor) {
-  auto& rootTransformNode = *transformTree().Node(kRealRootNodeId);
-  // TODO(jaydasika) : We shouldn't set ToScreen and FromScreen of root
-  // transform node here. They should be set while updating transform tree in
-  // cc.
-  gfx::Transform toScreen;
-  toScreen.Scale(deviceScaleFactor, deviceScaleFactor);
-  transformTree().SetToScreen(rootTransformNode.id, toScreen);
-  gfx::Transform fromScreen;
-  if (!toScreen.GetInverse(&fromScreen))
-    rootTransformNode.ancestors_are_invertible = false;
-  transformTree().SetFromScreen(rootTransformNode.id, fromScreen);
-  transformTree().set_needs_update(true);
+  auto& rootTransformNode = *transformTree().Node(kSecondaryRootNodeId);
+  rootTransformNode.local.Scale(deviceScaleFactor, deviceScaleFactor);
 }
 
 int PropertyTreeManager::compositorIdForTransformNode(